Re: Reunification - makes no sense?
Roddenberry died during filming of Hero Worship (5x11). Unification was 5x07-08. But I don't know the production orders of those two episodes.
ETA: Unification was produced before Hero Worship but had the Gene Roddenberry memorial title card when it aired.
Yes, Roddenberry was gone before Unification aired, but it had already been filmed.
"Beep... beep!" --Captain Pike